Table 2.
Defined daily dose (DDD) for concomitant AEDs
| AED | Approximately 2/3 DDD | Adult DDD |
|---|---|---|
| Carbamazepine* | 700 mg | 1000 mg |
| Ethosuximide | 800 mg | 1250 mg |
| Felbamate | 1600 mg | 2400 mg |
| Gabapentin | 1200 mg | 1800 mg |
| Levetiracetam | 1000 mg | 1500 mg |
| Lamotrigine* | 200 mg (200 mg with enzyme inducers; 100 mg with valproate) | 300 mg (400 mg with enzyme inducers; 150 mg with valproate) |
| Lacosamide† | 300 mg | 200–400 mg |
| Oxcarbazepine* | 700 mg (1000 mg with enzyme inducers) | 1000 mg (2000 mg with enzyme inducers) |
| Phenobarbital | 70 mg | 100 mg |
| Pregabalin | 200 mg | 300 mg |
| Phenytoin* | 200 mg | 300 mg |
| Primidone | 800 mg | 1250 mg |
| Tiagabine | 20 mg (30 mg with enzyme inducers) | 30 mg (60 mg with enzyme inducers) |
| Topiramate | 200 mg (300 mg with enzyme inducers) | 300 mg (600 mg with enzyme inducers) |
| Vigabatrin | 1400 mg | 2000 mg |
| Valproate | 1000 mg | 1500 mg |
| Zonisamide | 140 mg (200 mg with enzyme inducers) | 200 mg (400 mg with enzyme inducers) |
Note: The DDD is the assumed average maintenance dose per day for a drug used for its main indication in adults [32].
*Sodium channel blockers; †Adult DDD information from product label.
DDD = defined daily dose; AED = antiepileptic drug.